Conventionally a KAATSU muscle training method has been proposed, which is capable of strengthening muscles effectively by applying load to muscles while restricting blood circulation thereto, and such a method has been put to practice use (see Patent Document 1, for example). In such a muscle training method, a muscle strengthening tool is used, which is configured to apply pressure to a muscle while tightening a predetermined part of four limbs (arms and legs) of a user with a tightening tool.